25 Now when Moses saw that the people were out of control–for Aaron had let them get out of control to be a derision among their enemies– 26 then Moses stood in the gate of the camp, and said, “Whoever is for the LORD, come to me!” And all the sons of Levi gathered together to him. 27 He said to them, “Thus says the LORD, the God of Israel, `Every man of you put his sword upon his thigh, and go back and forth from gate to gate in the camp, and kill every man his brother, and every man his friend, and every man his neighbor.'” 28 So the sons of Levi did as Moses instructed, and about three thousand men of the people fell that day. 29 Then Moses said, “Dedicate yourselves today to the LORD–for every man has been against his son and against his brother–in order that He may bestow a blessing upon you today.”
God doesn’t tolerate sin, and He certainly doesn’t tolerate those who have no self-control, and lead His people astray by their sin. While He has compassion on those outside the church, and calls them to Himself, those inside the church who wallow in their sin are in a precarious place. In this passage, the penalty was death. God wasn’t kidding around. Sin is serious business, and if you let it control your life, there’s no telling the destruction and death it can produce in your life, even more so for those who call themselves Christians.